Nortel Networks Option 11C Manuale Utente
Spares planning
Page 193 of 544
NFT values
Table 59 translates NFT values to the number of spares required in stock:
N—Number in use
F—Failure rate
T—Turnaround time (in hours)
Table 59
Number of spares required (Part 1 of 2)
Number of spares required (Part 1 of 2)
NFT values
Number
of spares
0
0.0010
1
0.0010
0.0452
2
0.0452
0.1890
3
0.189
0.425
4
0.425
0.734
5
0.734
1.090
6
1.09
1.50
7
1.50
1.95
8
1.95
2.43
9
2.43
2.94
10
2.94
3.46
11
3.46
4.01
12
4.01
4.58
13
4.58
5.16
14
5.16
5.76
15
5.76
6.37
16